package com.ydj.reggie.controller;

import com.ydj.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

/**
 * @author ydj
 * @version 1.0
 */
@Slf4j
@RestController
@RequestMapping("/common")
public class CommonController {

    @Value("${reggie.path}")
    private String basePath;

    /**
     * 文件上传
     *
     * @param file 必须和前端的name相同
     * @return
     */
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file) {
        //file是一个临时文件，需要转存到指定位置，否则本次请求结束后临时文件会删除
        log.info(file.toString());

        //原始文件名
        String originalFilename = file.getOriginalFilename();
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));

        //使用UUID重新生成文件名，防止文件名重复造成文件覆盖
        String fileName = UUID.randomUUID().toString() + suffix;//加上文件后缀

        //创建一个目录对象
        File dir = new File(basePath);
        if (!dir.exists()){
            //目录不存在，需要创建
            dir.mkdirs();
        }

        try {
            file.transferTo(new File(basePath + fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return R.success(fileName);
    }

    /**
     * 文件下载
     * @param name 文件名
     * @param response
     */
    @GetMapping("/download")
    public void download(String name,HttpServletResponse response){
        try {
            //输入流，通过输入流读取文件内容
            FileInputStream inputStream = new FileInputStream(new File(basePath + name));

            //输出流，通过输出流将文件写会到浏览器中，在浏览器展示图片
            ServletOutputStream outputStream = response.getOutputStream();

            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bates = new byte[1024];
            while ((len = inputStream.read(bates)) != -1){
                outputStream.write(bates,0,len);
                outputStream.flush();
            }
            //关闭资源
            inputStream.close();
            outputStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }


    }
}
